The cystic fibrosis gene encodes a chloride channel (CFTR) that regulates transepithelial salt and water transport. Two classes of CFTR-binding proteins appear to link the opposing cytoplasmic tails of this channel to distinct regulatory networks. Such interactions may constitute new paradigms for modulating CFTR activity in health and disease.

The “sensory” circumventricular organs, with their leaky blood-brain barriers, permit contact between brain neurons and blood-borne molecules. Body fluid balance and cardiovascular control involve established interface functions of subfornical organs. Their recently identified target functions for hormones released during digestion suggest that they may coordinate fluid and food intake.

Virus particles that infect eukaryotic cells can take advantage of the cytoskeleton and associated motors to translocate through the cytoplasm. Depending on the virus, motor proteins are recruited or, alternatively, cytoskeletal elements are induced to polymerize onto viral structures. Here we review recent advances toward understanding the roles of the cytoskeleton in virus trafficking.

Glucose-stimulated insulin secretion consists of a transient first phase followed by a sustained second phase. Diabetes (type II) is associated with abnormalities in this release pattern. Here we review the evidence that biphasic insulin secretion reflects exocytosis of two functional subsets of secretory granules and the implications for diabetes.

Rapid and complete relaxation is a prerequisite for cardiac output adaptation to changes in loading conditions, inotropic stimulation, and heart rate. In the healthy human heart, the rate and extent of relaxation depend mainly on actomyosin cross bridge dissociation and on left ventricular end-systolic volume, rather than on the afterload level.

Glutamate is the main excitatory transmitter in the mammalian CNS, mediating fast synaptic transmission primarily by activation of AMPA-type glutamate receptor channels. Both synaptic structure and a cell-specific molecular switch in the AMPA receptor subunit expression are involved in the regulation of the synaptic signaling time course.

Active canalicular secretion of bile salts and non-bile salt organic anions represents the major driving force of hepatic bile formation. The most important carriers involved have now been cloned on both the basolateral and canalicular sides of hepatocytes. Elucidation of their structure, transport properties, and regulation is an important step forward in the ultimate understanding of the molecular physiology of bile formation.

Although many people suffer from orofacial pain and headache, objective methods for investigation of trigeminal nociception in humans have been lacking. Trigeminal brainstem reflexes such as the masseter inhibitory reflex and the blink reflex are mediated by central multireceptive neurons that are also involved in trigeminal nociception. Therefore, these trigeminal reflexes are suitable models for probing pontine and medullary pain processing.

Synaptic transmission has traditionally been studied at the level of the entire nerve terminal rather than at one of its constituent boutons. Autonomic ganglia provide preparations for recording from individual boutons, as well as for determining the calcium transients necessary for transmitter release at these boutons. The results suggest a new paradigm for synaptic transmission.

The condition of the respiratory system is more important for endurance exercise performance of healthy subjects than hitherto assumed. Not only do respiratory muscles fatigue during intensive endurance exercise, but prefatigued respiratory muscles can also impair performance. In turn, respiratory endurance training can improve endurance exercise performance.